39978293 has 2 divisors, whose sum is σ = 39978294. Its totient is φ = 39978292.

The previous prime is 39978287. The next prime is 39978311. The reversal of 39978293 is 39287993.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 39967684 + 10609 = 6322^2 + 103^2 .

It is an emirp because it is prime and its reverse (39287993) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 39978293 - 2⁶ = 39978229 is a prime.

It is a super-2 number, since 2×39978293² = 3196527822387698, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (39978233) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19989146 + 19989147.

It is an arithmetic number, because the mean of its divisors is an integer number (19989147).

Almost surely, 2^39978293 is an apocalyptic number.

It is an amenable number.

39978293 is a deficient number, since it is larger than the sum of its proper divisors (1).

39978293 is an equidigital number, since it uses as much as digits as its factorization.

39978293 is an evil number, because the sum of its binary digits is even.

The product of its digits is 734832, while the sum is 50.

The square root of 39978293 is about 6322.8389984247. The cubic root of 39978293 is about 341.9333140615.

The spelling of 39978293 in words is "thirty-nine million, nine hundred seventy-eight thousand, two hundred ninety-three".